Control mechanism for pressing machines



Sept. 5, 1939. G. w JOHNSON CONTROL MECHANISM FOR PRESSING MACHINES Filed Sept. 1, 1937 3 Sheets-Sheet l TQE INVENTOR SEEORGE W. JOHNSON Wfi 7f%= ATTORNEYS Sept. 5, 1939-. e. w. JOHNSON 2,171,570 CONTROL MECHANISM FOR FRESSING MACHINES Filed Sept. l, 1937 5 Sheets-Sheet 2 FIG-4 FIG-3 INVENTOR gI-IORGE W. JOHNSON mwwy ATTORN EYS Sept. 5, 1939. G. w. JOHNSON 2,171,570

CONTROL MECHANISM FOR PBESSING MACHINES Filed Sept 1, 1937 3 Sheets-Sheet 3 FIG-5 INVENTOR EORGE W. JOHNSON Patented Sept. 5, 1939 CONTROL MECHANISM FOR PRE S SING MACHINE S George W. Johnson, Cincinnati, Ohio, assignor to The American Laundry Machinery Company, Norwood, Cincinnati, Ohio, a corporation of Ohio Application September 1, 1937, Serial No. 161,911

4 Claims. (Cl. 192131) Ths invention relates to improvements in control mechanism for pressing machines, particularly of the type used in laundry and garment work.

An object of the present invention is to provide in a power closed pressing machine, control means for the power means including a pair of spaced safety manuals movable from unoperated position to an intermediate position for causing a closing movement of the pressing members, and from the intermediate position to a full operated position toengage a holding means for retaining the control means in actuated position so that the power means holds the press closed. Stop means is provided preventing movement of the manuals from-the intermediate position to the full operated position until the press is safely closed.

Other advantages of my control mechanism and noval features thereof will appear in the accompanying drawings and specification and the essential features will be summarized in the claims.

In the drawings, Fig. 1 is an end elevation of a pressing machine in open position, embodying my novel control mechanism; Fig. 2 is a diagram.- matic view of the control mechanism of the press in the position of Fig. 1; Fig. 3 is a view similar to Fig. 1, showing in full lines the press in safe closed position and in dot-dash lines the fully closed position; Fig. l is a diagrammatic view of the control mechanism corresponding to the position of the press parts just prior to reaching the full line position of Fig. 3; Fig. 5 is a diagrammatic View of the control mechanism of the pressing machine when it has reached the broken line position of Fig. 3; while Fig. 6 is a diagrammatic view showing a modified form of control mechanism.

I have illustrated my improved control mechanism as applied to a type of pressing machine used in laundry and garment work, comprising a frame I3 supporting a pressing bed II and pivotally supporting a yoke I2 which carries a pressing headIB into and out of engagement with the bed I I when actuated by the toggle I4 under the influence of motor I5. A spring I6 normally returns the head to open position.

In the form. illustrated I have shown a control valve for a power means l5 operated by means of 'a pilot valve which in turn is actuated by a pair of spaced safety manuals operating through a Whiffietree connection. However, my invention is equally applicable to any control means for the press closing power means operated by spaced safety manuals as hereinafter. described andineluding means for latching or otherwise holding the control means in operated position upon movement of both manuals to full operated position.

In the embodiment shown, the supply of fluid to motor I5 is by way of conduit ll, valve casing I8 and conduit I9. Valve casing IB houses a normally closed inlet valve I8a and a normally open outlet valve lab, both actuated by stem I80 and held in normal position by the spring I8d. With this type of valve the spring may be omitted if the valve is in horizontal position as the action of the air supply on the inlet valve ball produces a self-closing movement. The means here shown for actuating valve stem I80 comprises a servomotor 20 having a diaphragm 20a and a rod 20?) for engaging the valve stem I80. Fluid supply to motor 29 is by way of supply conduit I'l, conduit 2|, valve casing 22 and conduit 23. The structure within casing 22 is similar to that in casing I8 and the parts therof have been given similar suffixes. In this case the valve stem 220 has been provided with a yieldable end 22e.

Two-hand control means for causing actuation of the valves in casing 22 is provided. In the present instance manuals 24 and 25 are connected by links 26 with opposite ends of whiifletree 2'! which carries a bar 210. adapted to engage the valve stem 22e. Springs 28 normally bias the manuals to unoperated position.

Means is provided for holding the power control means in actuated position when the manuals are fully operated. In the present instance this holding means is a latch 29 on the valve stem end 22c and on oscillating keeper 30 pivotally mounted at 3| on the press frame and having an arm 30a operatively engaged by the operating rod 3Ia of the diaphragm servo-motor 3|. As shown, the arm 30a passes through a slotted opening in the rod 3 la. A spring 3127 normally biases the rod 3 la downwardly and the latch 30 in a clockwise direction toward its operative position as shown in Fig. 2. For releasing the latch power supply for motor 3| is provided through conduit 32, valve casing 33 and conduit 34. The structure of valve casing 33 is similar to that of casings I8 and 22 and the parts have been given similar reference characters. A release manual 33d serves to move the valves in casing 33 to actuated position so as to energize the servo-motor ;3I to release the latch.

Means is provided to prevent movement of manuals 24 and 25 beyond their intermediate position as shown in Fig. 4 to the full operated position as shown in Fig.5 ,until the press is safely closed. In the modification of Figs. 1 to 5, this means comprises two stops 35, one for each manual, rigidly mounted on a shaft 36 which is provided with an arm 31. This arm is connected by a rod 38 with a portion of the press mechanism. As shown in Figs, 1 and 3, this rod 38 extends through a slot in bracket 14a carried by the toggle and has a pair of collars 38a and 38b carried by the rod. A spring 39 normally biases the rod and the stop members to the position of Figs. 1 to 4. This allows movement of the manuals 24 and 25 to an intermediate position effective to actuate the valves in casings 22 and I8 so as to actuate motor but not sufli'cient to permit engagement of the latch members 29 and 30. The arrangement is such, however, that when the press is safely closed as shown in full lines in Fig. 3, the bracket I401. engages the collar 38a, whereupon further movement of the parts removes the stops 35 to the position of Fig. 5, thus permitting movement of manuals 24 and 25 from the intermediate position to the full operated position there shown. This action of the manuals is sufficient to engage the latch elements 29 and 33, spring 3Ib yielding to permit engagement of the latch.

It is thought that the operation of the above described device will now be clear. With the press in the open position of Fig. 1, the operator arranges the work on the bed H and depresses manuals 24 and 25 to the position of Fig. 4 where they engage the stops 35. Neither manual alone will cause actuation of the press because of the gap between the bar 21a and the valve stem end 226. However, coincidental actuation of both manuals moves the valves in casing 22 to the position of Fig. 4, whereupon pressure fluid flows through conduits l1 and 2|, valve casing 22 and conduit 23 to 'servomotor 20. The motor makes a stroke toward the left as viewed in the drawings, actuating the valves in casing 18 and supplying fluid to motor l5. This supply is through conduit ll, casing I8 and conduit |9.' The motor then moves the parts to the position shown in full lines in Fig. 3 which is the safe closed position where the operator can no longer get a hand caught between the pressing members. Until this position is reached the manuals cannot be moved beyond 'the position of Fig. 4 and release of either manual will cause the press to open. However, upon further movement the stops 35 are moved to the position of Fig.- 5 as toggle I4 straightens and as :the press parts approach the dot-dash position of Fig. 3. This permits actuation of manuals 24 and 25 to the full operated position of Fig.5 which is sufficient to engage the latch elements .29 and 30 whereupon the valves in casing 22 are held in actuated position thereby also holding the valves in casing H3 in actuated position and the press remains closed under fluid pressure. Both manuals may then be released and the press will remain in closed position. To open the press manual 33d is momentarily depressed, supplying fluid to servo-motor 3| and releasing the latch member 30, whereupon the valves in casing 22 return to the position of Fig. 2, evacuating servo-motor 20 andallowing valves in casing I8 to return to the position of Fig. 2, thus evacuating motor I5.and permitting the press to open under the influence of spring I6. 7

In the modification shown diagrammatically in Fig. 6, all of the parts are exactly as described before where they have been givensimilar reference characters. In this case, however, only one stop member is providednamely, the stop for manual 24-. This stop is carried by shaft 36 which carries an arm 31 connected with a rod 38 similar to the rod 38 described in connection with Figs. 1 to 5. In this modification manual 25 may be moved directly to full operated position but the latch 29-30 cannot be engaged until manual 24 is moved beyond the intermediate position shown in broken lines in Fig. 6. However, upon movement of the press parts to and beyond safe closed position the stop 40 is removed as previously described in connection with the stops 35 permitting manual 24 to be moved to its full operated position engaging the latch 29 and 30 as before and serving to hold the press closed when the manuals are released.

What I claim is:

1. In a pressing machine, a pair of relatively movable coacting pressing members, power means for causing a pressing operation between said members, normally unactuated control means for causing actuation of said power means, manual means for operating said control means and comprising 'two manuals spaced to require a hand of the operator on each of them for coincidental actuation thereof, means for moving said manuals .to unoperated position when they are released by the operator, said control means and manual means being so constructed and arrangedas to require coincidental operation of both manuals for effective actuation of said control means, said manual means having two stages of operation, a first stage adapted to actuate said control means to a position for energizing said power means and short of a maintained position whereby the pressing machine may be closed, and a second stage adapted to actuate said control means to a maintained position after the press reaches safe closed position, means normally preventing efiective second stage operation of said manual means, enabling means effective on said last named means and responsive to movement of the machine to safe closed position for permitting second stage operation of said manual means, latch means for holding said control means in actuated position, and said manual means being so-arranged that upon second stage operation thereof it moves said control means into latching engagement with said latch means, said latch means being releasable to permit said control means to return to unactuated position, and means to cause opening of said machine when said control means is in unactuated position.

2. In a pressing machine, a pair of relatively movable coacting pressing members, power means for causing a pressing operation between said members, normally unactuated control means for causing actuation of said power means, manual means for operating said control means and comprising two manuals spaced to require a hand of the operator on each of them for coincidental actuation thereof, meansfor moving said manuals to unoperated position when they are released by the operator, said control means and manual means being so constructed and ar- 'said control means to a maintained position after the press reaches safe closed position, means normally preventing effective second stage operation of said manual means, enabling means effective on said last named means and responsive to movement of the machine to safe closed position for permitting second stage operation of said manual means, latch means for holding said control means in actuated position and engageable upon second stage operation of said manual means, and said latch means when engaged being adapted to hold said control means in actuated position, whereupon said manuals may be released and will return to unoperated position, said latch means being releasable to permit said control means to return to unactuated position, and means to cause opening of said machine when said control means is in unactuated position.

3. In a pressing machine having relatively movable head and bed members and operating mechanism therefor, control means for said mechanism normally in unactuated position, actuating means for said control means including spaced manuals movable from unoperated to an intermediate position to produce operation of said mechanism and engagement approach movement of said members, and to a full operated position to maintain said members in engagement, means normally tending to move said manuals from intermediate or full operated position to unoperated position, means governed by the relative position of said movable members for controlling movement of said manuals Irom intermediate to full operated position, and releasable means for holding said control means in actuated position engageable by movement of said manuals to full operated position, there being means for causing opening of said machine when said control means is in unactuated position.?

4. In a pressing machine having relatively movable head and bed members and operating mechanism therefor, control means for said mechanism normally in unactuated position, latch means for holding said control means in actuated position, actuating means for said control means including spaced manuals movable from unoperated fto an intermediate position to produce operation of said mechanism and engagement approach movement of said members, and to a full operated position to cause engagement of said latch means, means normally tending to move said manuals from any position to unoperated position, stop means for said actuating means, and means operatively connecting said stop means with said mechanism for preventing movementaoi' an associated manual to full operated position except when said head and bed members are s a'fely closed, said latch means being releasable t'o permit said control means to return to unactuated position, and means to cause opening or said machine when said control means is in unactuated position.

GEORGE W. JOHNSON. 

